Camila dos Santos

Camila dos Santos speaks at the Pershing Square Research Alliance’s Fifth Annual Prize Dinner at the Park Avenue Armory on May 23 with Bill Ackman, co-founder of the Pershing Square Sohn Foundation and CEO of Pershing Square Capital Management, and Olivia Tournay Flatto, the President of the Pershing Square Foundation.

By Daniel Dunaief

They aren’t quite wonder twins, but some day the dedicated work of husband and wife scientists Christopher Vakoc and Camila dos Santos may help people batting against a range of cancers, from leukemia to breast cancer.

An assistant professor at Cold Spring Harbor Laboratory, dos Santos recently won the prestigious and highly coveted Pershing Square Sohn prize. Dos Santos, who studies breast cancer, will receive $200,000 in funds per year for the next three years. She won the same prize her husband, an associate professor at Cold Spring Harbor Laboratory, collected two years earlier for his work using the gene-editing technique CRISPR to study the molecular pathways involved in leukemia.

Dos Santos and Vakoc are the first family of prize winners in the Pershing Square Foundation’s five years of supporting research in the New York area.“The board was very much taken by how original her approach is and how thoughtful she is about it,” said Olivia Tournay Flatto, president of the foundation. “There was a lot of early stage data that would say that the observations she’s making are interesting to pursue, but that the National Institutes of Health would not fund. We felt this was something we wanted to be a part of.”

Dos Santos is studying so-called epigenetic changes that protect women from breast cancer if they become pregnant before they are 25. Women who have pregnancies before that cut-off age have a 30 to 40 percent decrease in breast cancer, even decades after their pregnancy.

Dos Santos has been digging into this process, looking at why some women who are pregnant before this age still develop breast cancer later in life.

The Cold Spring Harbor scientist is exploring how infections block the protective effects of pregnancy. She hasn’t defined the panel of infections that could influence cancer risk before or after pregnancy. The hypothesis in her work is that “the whole process that is fighting inflammation could change the breast cells,” which could “take away the advantage that pregnancy brings.”

If she proves her theory — that changes to inflammation could take away benefits of an early pregnancy — she could define changes to proteins and genes as biomarkers to predict the risk of breast cancer, even in the event of an early pregnancy. One of the challenges in the three-step application process for this prize was to explain to a group of experts how what she’s doing was different from what others are pursuing. Her approach is to look at cells before and during the process of turning into cancer cells. That strategy led to the current hypothesis, which was the basis for her application for this prize.

To study breast cancer, dos Santos recently developed a mouse model in her lab, to see how pregnancy changes pre-malignant lesions. When the mice they are studying have a gene that would turn into cancer, some of them don’t develop cancer if they’ve already been pregnant. Those mice that haven’t been pregnant develop cancer. She uses this mouse model to ask questions about how pregnancy changes a cell such that oncogenes cannot operate to change a cell into a cancer.

“We are not only investigating how prevention works, but we are also learning what signals break that prevention,” dos Santos said.

Dos Santos has used the mouse model experiments to test an unusual element to human breast cancer resistance. Women who reach their second trimester before 25, but don’t give birth to a child, have the same resistance, decades later, to breast cancer. Mice whose pregnancies last through the equivalent of the second trimester also experience similar epigenetic benefits.

She has tested mice who have a pseudo-pregnancy —who have higher pregnancy hormone levels without being pregnant — to see if a similar pregnancy environment would convey the same resistance. “Even in those cases, with no fetus, no embryo, no birth and no nursing, we see that the epigenetics changes,” dos Santos said. The scientist plans to use the funds from this award to perform high-tech experiments, such as single-cell, multiple mouse models and human tissue analysis that she wouldn’t have been able to tackle without the funding.

Dos Santos is grateful for the funding, which she said she wouldn’t have been able to secure through other means based on “the stage we are right now,” she said. The work is “risky” and “provocative,” but it’s also “outside of the box ideas and experiments and approaches.”

When she puts all the variants together, the risky outcome could be beneficial, leading to a better understanding of how to copy or, perhaps, understand nature to try to cure or prevent cancer.

Dos Santos said she learned about the award when she was on a train on the way to Jamaica, where she was catching a flight to Washington, D.C. She said she turned into a “texting machine,” sharing the good news with everyone, including her husband Vakoc, who called her as soon as he saw the news.“He was super happy,” she recalled.

She said Vakoc was particularly helpful in discussing the work and in watching their sons Lucas and Marcus who are 8 and 5, respectively. She also received some unexpected help from him before an extensive seven- to eight-minute finalist screening process.

She asked him about the interview, and he remembered that there were five people in the audience and that he didn’t get that many questions. When she appeared for her interview, she saw about 25 people in the audience and received numerous questions. In a way, she said, his memory of his experience may have helped her, because she didn’t have time to worry about the size of the audience or the number of questions.

Dos Santos said their sons are proud of their parents for winning awards for their work on cancer.

When her sons are upset with dos Santos, they sometimes warn, reflecting their parents’ threat to take away TV, that they’re going to “take your epigenetics away.”

Dos Santos said the couple maintains a healthy work-life balance. She is grateful for her husband’s support, as well as for the environment and expertise at Cold Spring Harbor Laboratory.

“Here at the lab, we not only have the technology to move this forward, but we also have a pretty outstanding body of scientists that are very collaborative,” she said.

Mothers of more than one child have blogged about it for years. When they have their second child, the breastfeeding process is often quicker, with milk available sooner than for the first child. Camila dos Santos, who became an assistant professor at Cold Spring Harbor Laboratory in February, has found a reason.

Cells in the mammary gland go through something called epigenetic changes. That means something affects the genetic machinery, causing them to react differently under the same circumstances. In mouse models, dos Santos discovered changes in cell proliferation and milk production genes to the hormones estrogen and progesterone.

When she was a postdoctoral student in Greg Hannon’s laboratory at CSHL, dos Santos said they “decided to profile the epigenome before and after pregnancy.” At first, she was looking for changes associated with the effects of pregnancy on breast cancer development. The recent work, however, described the presence of epigenetic memory of past pregnancies, which influences milk production in the next pregnancy.

The message from these studies was that those areas where she saw changes “are associated with the genes responsible for lactation and the proliferation of the mammary gland during pregnancy,” said dos Santos.

The implications of this research extend from the potential to enhance breastfeeding in women who struggle during lactation to breast cancer.

Indeed, other studies have shown that women who become pregnant before 25 have a lower risk for all types of breast cancer.

“We believe that such strong protective effect must have an epigenetic basis,” dos Santos said. She would like to “understand how this stable, pregnancy-induced epigenome prevents cancer development,” she continued.

Hannon believes the kind of research dos Santos is conducting holds promise.

“The world of breast cancer prevention is badly in need of very solid underlying molecular biology and I think there’s a fair chance that what [dos Santos] is doing will eventually get us there,” said Hannon, who recently left Cold Spring Harbor Laboratory and is now the Royal Society Wolfson Research Professor at the Cancer Research UK Cambridge Institute at the University of Cambridge.

Dos Santos said her research is exploring ways to turn the changes that occur during pregnancies before the age of 25 into a “preventive strategy to treat women that are high risk and even those that are not.”

To be sure, Hannon and dos Santos cautioned, it’s difficult to know how quickly or even whether this kind of research will lead to any treatment or prevention options.

“The main goal of my lab is to try to understand the effects of pregnancy on normal cells, to devise a strategy to prevent breast cancer from arising,” dos Santos said. She recently published her work in the journal Cell Reports.

Dos Santos and Andrew Smith, a computational biologist from the University of Southern California, along with his postdoctoral fellow Egor Dolzhenko discovered that mice that had been through a single pregnancy had methylation marks that were different from mice of the same age that hadn’t been pregnant. The group connected the changes in the genome to a transcription factor called Stat5a. A transcription factor is a protein that acts like a genetic traffic light, turning on or off genes.

When she joined Hannon’s lab in 2008, dos Santos wanted to study gene regulation throughout cell development. It took her three years to purify stem cells.

Hannon credits dos Santos for developing new techniques.

“She had to build the tools she needed to ask” these questions, Hannon said.

Dos Santos lives in campus housing with her husband, Christopher Vakoc, who is an assistant professor at CSHL. The couple take their young sons hiking and can’t wait for the spring and summer because they hike, swim and kayak. Vakoc and dos Santos met when they were in adjoining labs in Philadelphia.

“We used to have joint lab meetings and one day he asked me on a date,” she recalled.

This summer, dos Santos’ lab will include a premed undergraduate student from Hofstra and high school students from Cold Spring Harbor High School and Southampton High School. She recently hired a postdoctoral fellow.

“I envision my lab growing according to my needs,” she said. “Right now, I want to continue to work at the bench while training students and postdocs.”